WO2017187404A1

WO2017187404A1 - Solar and diesel generator based hybrid powered portable cold storage

Info

Publication number: WO2017187404A1
Application number: PCT/IB2017/052477
Authority: WO
Inventors: Devendra GUPTA; Vinay GUNASEKARAN; Vivek Pandey
Original assignee: Ecofrost Technologies Pvt. Ltd.
Priority date: 2016-04-29
Filing date: 2017-04-28
Publication date: 2017-11-02

Abstract

The present disclosure generally relates to the field of cooling and refrigeration. In particular, the present disclosure relates to a portable cold storage device that is powered through a hybrid power means having solar panel and diesel generator based powering capability. In an aspect, the present disclosure relates to a portable cold storage device that includes a refrigeration compartment and a thermal energy storage unit, wherein the cold storage device is powered by a hybrid power means that include a solar based powering means that is configured to power the cold storage through one or more solar panels, and a diesel generator based powering means that is configured to power the cold storage through a diesel generator. In an aspect, activation of the solar based powering means and/or of the diesel generator based powering means can be controlled by means of a control system that is operatively coupled with the cold storage device.

Description

SOLAR AND DIESEL GENERATOR BASED HYBRID POWERED PORTABLE

COLD STORAGE

TECHNICAL FIELD

[0001] The present disclosure generally relates to the field of cooling and refrigeration. In particular, the present disclosure relates to a portable cold storage device that is powered through a hybrid power means having solar panel and diesel generator based powering capability.

BACKGROUND

[0002] Background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.

[0003] For any fruit and vegetable produce, perishability, that is, deterioration in its quality with lapse of time after it is harvested is a major issue. Due to unavoidable delays in the supply chain, quality of a sizable quantity of produce deteriorates by the time it reaches consumers. Perishability is responsible for high marketing costs, market gluts, price fluctuations, and other similar problems. At low temperature, perishability is considerably reduced and the shelf life increased. Such low temperatures are possible via refrigerating the produce in a Cold Storage. Hence, a reliable cold storage is of extreme importance in extending the shelf life of the fruit or vegetable produce without loss in its quality.

[0004] A reliable cold storage, in turn, requires that steady appropriate, generally low temperature is maintained irrespective of heat load which could change frequently. While refrigeration systems aim to achieve such steady low temperatures, they in turn depend upon an uninterrupted power supply source, usually a fixed grid electric supply. Cold storage usually have different heat load demands depending upon varying factors such as ambient temperature (which in turn depends upon weather, time of day or night), type, and quantity of items to be stored to name a few. Cold storage should therefore be able to maintain steady low temperature sunder these varying heat load conditions and should have low energy demand in order to be highly efficient.

[0005] On account of unpredictable demand and availability of transportation means there may be temporary requirement of cold storage to store perishable produce near the point of production or point of loading. Portable cold storage can meet such exigencies and play an integral role in supply chain for such products. Such portable cold storage can be swiftly moved to place of requirement to store such perishable goods for such periods as may be required by market conditions. As these portable refrigeration or cold storage units may be required to be deployed in remote locations, they cannot depend on a fixed grid electric supply and depend on mobile powering means such as IC engines to meet their power requirement. Use of such powering means increases cost of preservation effecting competitiveness of such goods.

[0006] Cost of preservation/storage can be reduced by using renewable power sources such as solar energy based powering, however, solar energy is not viable as only means as solar power is dependent on weather, time of day, season, intensity, panel alignment, among other like environmental/constructional conditions. For this reason the conventional portable cold storages typically depend on DG sets for their power requirement. However, cost of preservation can be reduced appreciably by providing power from alternate powering means such as solar power that can be utilized when available or to the extent available.

[0007] There is therefore a need in the art for a portable cold storage device and construction thereof that enables powering them using hybrid power means.

[0008] All publications herein are incorporated by reference to the same extent as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.

[0009] As used in the description herein and throughout the claims that follow, the meaning of "a," "an," and "the" includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of "in" includes "in" and "on" unless the context clearly dictates otherwise.

[0010] All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g. "such as") provided with respect to certain embodiments herein is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention. OBJECTS OF THE INVENTION

[0011] It is an object of the present disclosure to provide a portable cold storage unit that can be operated at reduced cost.

[0012] It is another object of this disclosure to provide a cold storage unit that can be powered by a hybrid power source having a solar panel based power source and a diesel generator based power source, operating individually or in combination.

[0013] It is another object of this disclosure to provide a cold storage unit that can be powered by a hybrid power source having a solar panel based power source and uses power from the solar panel based power source when available and to the extent available.

[0014] Yet another object of the disclosure is to provide a simple and reliable cold storage device for refrigerating perishable items in remote locations having limited and varying power supply.

[0015] With these and other objects, advantages and features of the invention may become apparent and the nature of the invention may be more clearly understood by reference to the following detailed description of the invention, the appended claims and the drawings attached hereto.

SUMMARY OF THE INVENTION

[0016] The present disclosure generally relates to the field of cooling and refrigeration. In particular, the present disclosure relates to a portable cold storage device that is powered through a hybrid power means having solar panel and diesel generator based powering capability.

[0017] In an aspect, the present disclosure relates to a portable cold storage device that includes a refrigeration compartment and a thermal energy storage unit, whereinthe cold storage device is powered by a hybrid power means that include a solar based powering means that is configured to power the cold storage through one or more solar panels, and a diesel generator based powering means that is configured to power the cold storage through a diesel generator. In an aspect, activation of the solar based powering means and/or of the diesel generator based powering means can be controlled by means of a control system that is operatively coupled with the cold storage device.

[0018] In an aspect the thermal energy storage unit can be charged when the solar power is in excess of what is required at that point of time by the refrigeration compartment and the thermal energy storage unit can be used to power up the refrigeration compartment when the solar power is not available or is not sufficient. The generator can be used when there isn't enough solar power available and there is no back-up from the thermal energy storage unit for sustained cooling of the refrigeration compartment. Thermal energy storage unit working as back-up results in increased operational efficiency of solar panels and minimizes the cost due to diesel generator operation. In an exemplary implementation, the thermal energy storage unit can alternatively be charged by diesel generation, if solar power is not available.

[0019] In another aspect, the cold storage device is portable, wherein the portability of the cold storage device is enabled by means of any or a combination of wheels or engine or magnetic force.

[0020] In another aspect, the cold storage device can include a variable speed compressor that can be powered through the hybrid power means. In an aspect, the hybrid power means can be operatively coupled with the variable speed compressor by means of an electrical motor drive, wherein the electrical motor drive can be configured to operate on AC or DC power based on characteristics of the variable speed compressor. In another aspect, the variable speed compressor can be configured to supply refrigerant to any or both of the refrigeration compartment and the thermal energy storage unit.

[0021] In an aspect, at least one component of the cold storage device can be configured such that the component is not powered by the hybrid power means. In another aspect, at least one component of the cold storage device can be powered by a battery, wherein the battery can be powered by the hybrid power means.

[0022] In yet another aspect, the one or more solar panels are adjustable. In another aspect, the control system can be configured to select any or both of the solar based powering means and the diesel generator based powering means based on any or a combination of ambient temperature, room temperature, rate of cooling required, solar power availability, time for which the power means is required, operational costs, time of day, location of the cold storage, and cooling attributes of the cold storage.

[0023] In yet another aspect, the control system can be configured to use a switching means that can be configured between the solar based powering means and the diesel generator based powering means to switch between the hybrid power means. In an aspect, the switching means can include one or a combination of a solid state relay, a contactor, a switch, electromechanical relay circuit, and a delay-off switch.

[0024] In another aspect, the diesel generator based powering means can be operatively coupled with a rectifier to convert AC output of diesel generator to DC. [0025] According to one embodiment, the cold storage device can include any or a combination of a thermal energy storage backup means, valves, fans, indoor cooling unit, one or more expansion valves, evaporator, and a power system.

[0026] Other features of embodiments of the present invention will be apparent from accompanying drawings and from detailed description that follows.

BRIEF DESCRIPTION OF THE DRAWINGS

[0027] FIG. 1 is an exemplary representation of the proposed portable cold storage device in accordance with an embodiment of the present disclosure.

[0028] FIG. 2 is an exemplary representation showing control system operated switch/relay based powering of the proposed cold storage device in accordance with an embodiment of the present disclosure.

DETAILED DESCRIPTION OF THE INVENTION

[0029] The following is a detailed description of embodiments of the disclosure depicted in the accompanying drawings. The embodiments are in such detail as to clearly communicate the disclosure. However, the amount of detail offered is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure as defined by the appended claims.

[0030] Each of the appended claims defines a separate invention, which for infringement purposes is recognized as including equivalents to the various elements or limitations specified in the claims. Depending on the context, all references below to the "invention" may in some cases refer to certain specific embodiments only. In other cases it will be recognized that references to the "invention" will refer to subject matter recited in one or more, but not necessarily all, of the claims.

[0031] The present disclosure generally relates to the field of cooling and refrigeration. In particular, the present disclosure relates to a portable cold storage device that is powered through a hybrid power means having solar panel and diesel generator based powering capability. In an aspect, the present disclosure relates to a portable cold storage device that includes a refrigeration compartment and a thermal energy storage unit, wherein the cold storage device is powered by a hybrid power means that include a solar based powering means that is configured to power the cold storage through one or more solar panels, and a diesel generator based powering means that is configured to power the cold storage through a diesel generator. In an aspect, activation of the solar based powering means and/or of the diesel generator based powering means can be controlled by means of a control system that is operatively coupled with the cold storage device.

[0032] In another aspect, the cold storage device is portable, wherein the portability of the cold storage device is enabled by means of any or a combination of wheels or engine or magnetic force.

[0033] In another aspect, the cold storage device can include a variable speed compressor that can be powered through the hybrid power means. In an aspect, the hybrid power means can be operatively coupled with the variable speed compressor by means of an electrical motor drive, wherein the electrical motor drive can be configured to operate on AC or DC power based on characteristics of the variable speed compressor. In another aspect, the variable speed compressor can be configured to supply refrigerant to any or both of the refrigeration compartment and the thermal energy storage unit.

[0034] In an aspect, at least one component of the cold storage device can be configured such that the component is not powered by the hybrid power means. In another aspect, at least one component of the cold storage device can be powered by a battery, wherein the battery can be powered by the hybrid power means.

[0035] In yet another aspect, the one or more solar panels are adjustable. In another aspect, the control system can be configured to select any or both of the solar based powering means and the diesel generator based powering means based on any or a combination of ambient temperature, room temperature, rate of cooling required, solar power availability, time for which the power means is required, operational costs, time of day, location of the cold storage, and cooling attributes of the cold storage. In yet another aspect, the control system can be configured to use a switching means that can be configured between the solar based powering means and the diesel generator based powering means to switch between the hybrid power means. In an aspect, the switching means can include one or a combination of a solid state relay, a contactor, a switch, electromechanical relay circuit, and a delay-off switch.

[0036] In another aspect, the diesel generator based powering means can be operatively coupled with a rectifier to convert AC output of diesel generator to DC.

[0037] According to one embodiment, the cold storage device can include any or a combination of a thermal energy storage backup means, valves, fans, indoor cooling unit, one or more expansion valves, evaporator, and a power system. [0038] FIG. 1 is an exemplary representation of the proposed portable cold storage device 100 in accordance with an embodiment of the present disclosure. As shown, the portable cold storage device 100 can be supported by means of a plurality of wheels 102 to enable convenient and easy transportation of the device 100 from one location to another. Apart from wheels, any other mechanism such as rails, magnetic force, engine, among others can be incorporated to make the cold storage device portable.

[0039] According to one embodiment, the cold storage device 100 can be powered through a hybrid power means 130 having solar panel 104 and diesel generator 106 based powering capability. In an aspect, the present disclosure relates to a portable cold storage device 100 that includes a refrigeration compartment 108 and a thermal energy storage unit 110, wherein the cold storage device 100 can be powered by a hybrid power means that include a solar based powering means that is configured to power the cold storage through one or more solar panels 104, and a diesel generator based powering means that is configured to power the cold storage through a diesel generator 106. In an aspect, activation of the solar based powering means and/or of the diesel generator based powering means can be controlled by means of a control system 112 that can be operatively coupled with the cold storage device 100.

[0040] According to an embodiment, the cold storage device 100 can incorporate means to merge power from solar panel and DG power means so that power to the extent available from the solar panels is fully utilized with corresponding reduction in requirement of power from DG power means. Such a situation may arise in mornings and evenings when power from sun light may not be adequate and when even the backup by the thermal energy storage unit is not enough to meet full power requirement of the device 100.

[0041] In another aspect, the cold storage device 100 can include a variable speed compressor 114 that can be powered through the hybrid power means 130. In an aspect, the hybrid power means can be operatively coupled with the variable speed compressor 114 by means of an electrical motor drive 116, wherein the electrical motor drive 116 can be configured to operate on AC or DC power based on characteristics of the variable speed compressor 114. In another aspect, the variable speed compressor 114 can be configured to supply refrigerant to any or both of the refrigeration compartment 108 and the thermal energy storage unit 110.

[0042] In another aspect, at least one component of the cold storage device 100 can be powered by a battery 126, wherein the battery can be powered by the hybrid power means. [0043] In yet another aspect, the one or more solar panels 104 are adjustable. In another aspect, the control system 112 can be configured to select any or both of the solar based powering means and the diesel generator based powering means based on any or a combination of ambient temperature, room temperature, rate of cooling required, solar power availability, time for which the power means are required, operational costs, time of day, location of the cold storage, and cooling attributes of the cold storage. In yet another aspect, the control system 112 can be configured to use a switching means that can be configured between the solar based powering means and the diesel generator based powering means to switch between the hybrid power means. In an aspect, the switching means can include one or a combination of a solid state relay, a contactor, a switch, electromechanical relay circuit, and a delay-off switch.

[0044] In another aspect, the diesel generator based powering means can be operatively coupled with a rectifier 206 (with reference to FIG. 2) to convert AC output of diesel generator 106 to DC.

[0045] According to one embodiment, the cold storage device 100 can include any or a combination of a thermal energy storage backup means, valves, fans, indoor cooling unit, one or more expansion valves, evaporator, a power system, among other components/parts that typically form part of a refrigeration device.

[0046] Aspects of the present disclosure therefore pertain to a portable solar powered cold storage 100 with hybridization of a diesel generator 106. The present disclosure further relates to a solar powered portable cold storage system 100 with diesel hybridization, wherein the system 100 includes an insulated container that can store produce to be cooled, and wherein the system 100 operates on a vapour compression technology where a compressor 114 is powered using either solar panels or by using diesel generator set. The rest of the electrical system (fan, valves, control system etc.) may be powered by a battery, which can be charged by either solar panels 104 or a diesel generator (DG) 106 using relevant charge controllers as and when required. The power source (solar or DG) can be interfaced with the compressor 114 using an electrical motor drive 116, wherein the system can further include, but is not limited to, any or a combination of an indoor cooling unit, a back-up thermal storage, an expansion valve, and a control and power system.

[0047] According to one embodiment, the proposed device 100 can remain stationary with solar panels 104 placed on the rooftop, and diesel generator 106 integrated with the system 100, or it can be moved on a truck/trailer with solar panel 104 being or not being kept on the rooftop. The system can have structural provisions for lifting the entire system 100 using cranes or forklifts or other mechanisms. The cooling can happen on the go using any or both of the power sources or the cooling can be maintained using the thermal storage backup. In an aspect, priority of the power source can be configured to remain as solar panels, wherein the control system 112 can decide the power source that would work best in a particular scenario on the basis of several factors including but not limited to ambient temperature, room temperature, rate of cooling required, solar power availability, among other like parameters. In order to switch between the power sources, a switch can be present, which may be solid state relay or a contactor or any other type of switch that can be controlled on the basis of any type of signal. The power can be supplied to the electric motor drive 116 in form of DC, wherein, in order to do this, an appropriately sized rectifier 206 can be used to convert the AC output of the diesel generator to DC. The solar panel(s) 104 can be configured to produce DC voltage, wherein stringing of the panels 104 can be adjusted as per required or an appropriately sized boost can be used to provide the required voltage to the electric motor drive. The diesel generator 106can preferably be a single phase output system. In an alternate embodiment, a 3 phase DG can also be used. In an aspect, the electric motor drive 116 can be configured to operate on DC, AC, or any other waveform based power supply based on the characteristics of compressor being used.

[0048] In an aspect, schematic of the powering system has been shown with reference to FIG. 2. As shown, the system 200 can include a control system 112 that be coupled with a solar panel based powering system 202, and with a diesel generator based powering system 204, by means of respective one or more switches/relays 208, wherein based on one or more pre-defined conditions, control signals can be issued by the control system 112 for operating the relays 208 to either activate the solar panel based powering system 202 or to activate the diesel generator based powering system 204 or activate both the powering systems. Based on the selection of the powering mechanism from the hybrid power means, the output can be connected to an electrical motor drive 116 that can be operatively coupled to run the compressor 114. In an aspect, as mentioned above, power supplied to the drive can be DC power, and as the DG 106 generates AC power, a rectifier 206 can be configured to convert AC output to DC.

[0049] In an aspect, cold storage device of the present disclosure can be provided with a plurality of wheels 102, a plurality of lifting tackles 134 and one or more tows 132 to enable it to be wheeled as well as lifted easily by readily available machineries such as Towing Machines and Cranes as per requirement.

[0050] In another exemplary implementation, a motor, a controller, and a mount mechanism can be provided on the solar cell panels in order for them to track the Sun according to azimuthal, elevation, and time factors programmed in the proposed control system 112. Within each 24 hour period, each cycle has a start time established by the time of Sunrise, a tracking phase, and a recycle phase. During the tracking phase, the Sun can be tracked in the most optimal fashion till Sunset, and during the recycle phase that is accomplished during night time, the Solar Panel is returned to an appropriate start point for the subsequent cycle that starts with sunrise the next day. In this fashion, the solar panels are positioned to deliver the maximum solar power to the proposed cold storage system at all times during the day.

[0051] In an aspect, a plurality of batteries can be configured in the cold storage device 100 to power one or more components, wherein the batteries may be charged as an when required by the power source(s) selected as above and are in turn used to supply appropriate DC or AC (via an inverter) power to the Cold Storage ancillariesl28 such as lights, fan, among other like components.

[0052] As shown above, the variable speed compressor 114 can be coupled to a variable speed motor 116, thermal energy storage unitl lO, cold storage refrigeration compartment 108, components of the vapour refrigeration system such as condenser 118, condenser fan 120, modulating valve 122 in the refrigerant pipeline for the thermal energy storage unit, modulating valve 124 in the refrigerant pipeline of the cold storage refrigeration compartment, and control System 112 for the whole system. The proposed device 100 can further include one or more sensors, relays, heat exchangers, filters, driers, among others, all of which can go in a refrigeration system. In an exemplary implementation, thermal storage compartment/unit can be inside the room with its cold surfaces exposed, from which heat transfer can take place via convection and/or radiation cooling.

[0053] In an aspect, the proposed device also enables incorporation of a Thermal Energy Storage Unit, wherein any power available over that demanded by the Cold Storage Refrigeration Compartment can be used to cool the Thermal Energy Storage Unit and/or charge the batteries whichever is more important at the time. In an alternate mode, when power available is less than that required by the Cold Storage Refrigeration Compartment extra the deficiency in cooling capacity is made up from the Thermal Energy Storage Unit. In the eventuality of no power being available, the Thermal Energy Storage Unit can provide several hours of backup thus keeping the produce in the Cold Storage Refrigeration Compartment safe from deterioration.

[0054] According to another embodiment, control system 112 of the present disclosure can include a series of programmable microcontrollers of various types taking control signals from sensors for temperature, pressure, humidity etc. and then executes a series of protocols to issue instructions indicative of which powering means and to what extent should be retrieved so as to minimize the cost of external energy intake.

[0055] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

[0056] It will be further understood that the terms "comprises" or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, or components, but do not preclude or rule out the presence or addition of one or more other features, integers, steps, operations, elements, components, or groups thereof.

[0057] The use of the expression "at least" or "at least one" suggests the use of one or more elements, as the use may be in one of the embodiments to achieve one or more of the desired objects or results.

[0058] The process steps, method steps, algorithms or the like may be described in a sequential order, such processes, methods and algorithms may be configured to work in alternate orders. In other words, any sequence or order of steps that may be described does not necessarily indicate a requirement that the steps be performed in that order. The steps of processes described herein may be performed in any order practical. Further, some steps may be performed simultaneously, in parallel, or concurrently.

[0059] The aim of this specification is to describe the invention without limiting the invention to any one embodiment or specific collection of features. Person skilled in the relevant art may realize the variations from the specific embodiments that will nonetheless fall within the scope of the invention.

[0060] It may be appreciated that various other modifications and changes may be made to the embodiment described without departing from the spirit and scope of the invention. ADVANTAGES OF INVENTION

[0061] The present disclosure provides a portable cold storage unit that can be easily transported.

[0062] The present disclosure provides a cold storage unit that can be used with hybrid power source having a solar panel based power source and diesel generator based power source, operating individually or in combination.

[0063] The present disclosure provides a simple and reliable cold storage device for refrigerating perishable items in remote locations having limited and varying power supply.

Claims

We Claim:

1. A cold storage device comprising a refrigeration compartment, wherein the cold storage device is portable.

2. The cold storage device of claim 1, wherein portability of the cold storage device is enabled by means of any or a combination of wheels or engine or magnetic force.

3. The cold storage device of claim 1, wherein the cold storage device is powered by a hybrid power means, wherein the hybrid power means comprises a solar based powering means that is configured to power the cold storage through one or more solar panels, and wherein the hybrid power means further comprises a diesel generator based powering means that is configured to power the cold storage through a diesel generator, and wherein activation of said solar based powering means and/or said diesel generator based powering means is controlled by means of a control system that is operatively coupled with the cold storage device.

4. The cold storage device of claim 3, wherein the cold storage device comprises a variable speed compressor, and wherein the variable speed compressor is powered through the hybrid power means.

5. The cold storage device of claim 4, wherein the hybrid power means is operatively coupled with the variable speed compressor by means of an electrical motor drive, and wherein the electrical motor drive is configured to operate on AC or DC power based on characteristics of the variable speed compressor.

6. The cold storage device of claim 4, wherein the variable speed compressor supplies refrigerant to any or both of the refrigeration compartment and the thermal energy storage unit.

7. The cold storage device of claim 3, wherein at least one component of the cold storage device is not powered by the hybrid power means.

8. The cold storage device of claim 3, wherein at least one component of the cold storage device is powered by a battery, and wherein the battery is powered by the hybrid power means.

9. The cold storage device of claim 3, wherein the control system selects any or both of the solar based powering means and the diesel generator based powering means based on any or a combination of ambient temperature, room temperature, rate of cooling required, solar power availability, time for which the power means is required, operational costs, time of day, location of the cold storage, and cooling attributes of the cold storage.

10. The cold storage device of claim 3, wherein the control system uses a switching means that is configured between the solar based powering means and the diesel generator based powering means to switch between the hybrid power means.

11. The cold storage device of claim 10, wherein the switching means comprise one or a combination of a solid state relay, a contactor, a switch, electromechanical relay circuit, and a delay-off switch.

12. The cold storage device of claim 3, wherein the diesel generator based powering means is operatively coupled with a rectifier to convert AC output of diesel generator to DC.

13. The cold storage device of claim 3, wherein the cold storage device comprises any or a combination of a thermal energy storage backup means, valves, fans, indoor cooling unit, one or more expansion valves, evaporator, and a power system.